BRAINCAKEReactivity Trends
Revision notes for Reactivity Trends in OCR Chemistry A (H032). Read the start of any lesson here, then sign in free for the whole lesson, the R.E.C.I.P.E. recall steps and the quiz.
- Group 2 elements as Reducing AgentsThe elements in group 2 are the alkaline earth metals and have two electrons in the outermost shell.
- Group 2 Redox Reactions with OxygenGroup 2 metals all react with oxygen to form metal oxides.
- Group 2 Redox Reactions with WaterThe group 2 elements react with water to form alkaline hydroxides with the general formula M(OH)2 and hydrogen gas.
- Group 2 Redox Reactions with Dilute AcidsAll group 2 metals undergo redox reactions with dilute with acids to form a salt and hydrogen gas. metal + acid → salt + hydrogen The reactivity…
- Group 2 Reactivity and Ionisation EnergyThe reactivity of redox reactions increases down group 2.
- Reactions of Group 2 OxidesGroup 2 oxides react with water and release hydroxide ions to form alkaline solutions.
- Solubility of Group 2 HydroxidesThe solubility of Group 2 hydroxides increases down the group.
- Uses of Group 2 CompoundsCalcium hydroxide is added to the soil as lime to increase the pH of acidic soils.
- Group 7 Halogens Trends in Boiling PointsThe halogens exist as diatomic molecules X2 at room temperature and pressure.
- Group 7 Redox Reactions and ReactivityEach halogen has seven outer shell electrons.
- Halogen-Halide Displacement ReactionsA more reactive halogen will displace a less reactive halide from a solution of its salt.
- Halogen Disproportionation ReactionsDisproportionation is a redox reaction in which the same element is both oxidised and reduced.
- Uses of HalogensFluoride is added to drinking water and toothpaste to prevent tooth decay.
- Test for Halide IonsAqueous silver nitrate is added to a solution of the halide.
- Test for AnionsTest for Carbonates Carbonates react with acids to form carbon dioxide gas.
- Test for Ammonium IonsAqueous sodium hydroxide, NaOH, is added to the solution to be tested.